/*
 * Copyright (c) 2025, 2025, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.oracle.svm.hosted.webimage.wasmgc.ast;

import com.oracle.svm.hosted.webimage.wasm.ast.ModuleField;
import com.oracle.svm.hosted.webimage.wasm.ast.id.WasmId;

/**
 * Definition for a Wasm type. In particular, this corresponds to the {@code typedef} symbol in the
 * <a href="https://webassembly.github.io/gc/core/text/types.html#text-rectype">WasmGC Spec</a>.
 * <p>
 * In WasmGC, a type can be final (meaning, no subtypes of it can exist) and it can optionally have
 * a supertype. All subtype relations between types have to be explicit by declaring supertypes. No
 * two types (not even function types) are implicitly sub and supertypes even if they are
 * structurally compatible.
 */
public abstract class TypeDefinition extends ModuleField {

    /**
     * The {@link WasmId} used to refer to this type.
     */
    private final WasmId.Type id;

    /**
     * Optional supertype.
     */
    public final WasmId.Type supertype;

    public final boolean isFinal;

    protected TypeDefinition(WasmId.Type id, WasmId.Type supertype, boolean isFinal, Object comment) {
        super(comment);
        this.id = id;
        this.supertype = supertype;
        this.isFinal = isFinal;
    }

    public WasmId.Type getId() {
        return id;
    }

    @Override
    public String toString() {
        return "TypeDefinition{id=" + id +
                        ", supertype=" + supertype +
                        ", isFinal=" + isFinal +
                        ", comment=" + comment +
                        '}';
    }
}
